443 research outputs found

    Six and seven loop Konishi from Luscher corrections

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    In the present paper we derive six and seven loop formulas for the anomalous dimension of the Konishi operator in N=4 SYM from string theory using the technique of Luscher corrections. We derive analytically the integrand using the worldsheet S-matrix and evaluate the resulting integral and infinite sum using a combination of high precision numerical integration and asymptotic expansion. We use this high precision numerical result to fit the integer coefficients of zeta values in the final analytical answer. The presented six and seven loop results can be used as a cross-check with FiNLIE on the string theory side, or with direct gauge theory computations. The seven loop level is the theoretical limit of this Luscher approach as at eight loops double-wrapping corrections will appear.Comment: 18 pages, typos correcte

    Non-planar ABJM Theory and Integrability

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    Using an effective vertex method we explicitly derive the two-loop dilatation generator of ABJM theory in its SU(2)xSU(2) sector, including all non-planar corrections. Subsequently, we apply this generator to a series of finite length operators as well as to two different types of BMN operators. As in N=4 SYM, at the planar level the finite length operators are found to exhibit a degeneracy between certain pairs of operators with opposite parity - a degeneracy which can be attributed to the existence of an extra conserved charge and thus to the integrability of the planar theory. When non-planar corrections are taken into account the degeneracies between parity pairs disappear hinting the absence of higher conserved charges. The analysis of the BMN operators resembles that of N=4 SYM. Additional non-planar terms appear for BMN operators of finite length but once the strict BMN limit is taken these terms disappear.Comment: 1+26 pages, uses axodraw.sty. v2: typos fixed, references added. v3: more typos fixed, minor correction

    Exceptional Operators in N=4 super Yang-Mills

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    We consider one particularly interesting class of composite gauge-invariant operators in N=4 super Yang-Mills theory. An exceptional feature of these operators is that in the Thermodynamic Bethe Ansatz approach the one-loop rapidities of the constituent magnons are shown to be exact in the 't Hooft coupling constant. This is used to propose the mirror TBA description for these operators. The proposal is shown to pass several non-trivial checks.Comment: 40 pages, 2 figures, 1 attached Mathematica noteboo

    Double-logs, Gribov-Lipatov reciprocity and wrapping

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    We study analytical properties of the five-loop anomalous dimension of twist-2 operators at negative even values of Lorentz spin. Following L. N. Lipatov and A. I. Onishchenko, we have found two possible generalizations of double-logarithmic equation, which allow to predict a lot of poles of anomalous dimension of twist-2 operators at all orders of perturbative theory from the known results. Second generalization is related with the reciprocity-respecting function, which is a single-logarithmic function in this case. We have found, that the knowledge of first orders of the reciprocity-respecting function gives all-loop predictions for the highest poles. Obtained predictions can be used for the reconstruction of a general form of the wrapping corrections for twist-2 operators.Comment: 17 pages, references adde

    Strings in AdS_4 x CP^3: finite size spectrum vs. Bethe Ansatz

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    We compute the first curvature corrections to the spectrum of light-cone gauge type IIA string theory that arise in the expansion of AdS4×CP3AdS_4\times \mathbb{CP}^3 about a plane-wave limit. The resulting spectrum is shown to match precisely, both in magnitude and degeneration that of the corresponding solutions of the all-loop Gromov--Vieira Bethe Ansatz. The one-loop dispersion relation correction is calculated for all the single oscillator states of the theory, with the level matching condition lifted. It is shown to have all logarithmic divergences cancelled and to leave only a finite exponentially suppressed contribution, as shown earlier for light bosons. We argue that there is no ambiguity in the choice of the regularization for the self-energy sum, since the regularization applied is the only one preserving unitarity. Interaction matrices in the full degenerate two-oscillator sector are calculated and the spectrum of all two light magnon oscillators is completely determined. The same finite-size corrections, at the order 1/J, where JJ is the length of the chain, in the two-magnon sector are calculated from the all loop Bethe Ansatz. The corrections obtained by the two completely different methods coincide up to the fourth order in λ=λ/J2\lambda' =\lambda/J^2. We conjecture that the equivalence extends to all orders in λ\lambda and to higher orders in 1/J.Comment: 32 pages. Published version; journal reference adde

    Scattering of Giant Magnons in CP^3

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    We study classical scattering phase of CP^2 dyonic giant magnons in R_t x CP^3. We construct two-soliton solutions explicitly by the dressing method. Using these solutions, we compute the classical time delays for the scattering of giant magnons, and compare them to boundstate S-matrix elements derived from the conjectured AdS_4/CFT_3 S-matrix by Ahn and Nepomechie in the strong coupling limit. Our result is consistent with the conjectured S-matrix. The dyonic solutions play an essential role in revealing the polarization dependence of scattering phase.Comment: 29 pages; v2: minor corrections; v3: minor corrections, references added ; v4: minor corrections ; v5: minor corrections based on the published versio

    Konishi operator at intermediate coupling

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    TBA equations for two-particle states from the sl(2) sector proposed by Arutyunov, Suzuki and the author are solved numerically for the Konishi operator descendent up to 't Hooft's coupling lambda ~ 2046. The data obtained is used to analyze the properties of Y-functions and address the issue of the existence of the critical values of the coupling. In addition we find a new integral representation for the BES dressing phase which substantially reduces the computational time.Comment: lots of figures, v2: improved numerics, c1=2, c2=0, c4 does not vanis

    Comments on the Mirror TBA

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    We discuss various aspects of excited state TBA equations describing the energy spectrum of the AdS_5 \times S^5 strings and, via the AdS/CFT correspondence, the spectrum of scaling dimensions of N = 4 SYM local operators. We observe that auxiliary roots which are used to partially enumerate solutions of the Bethe-Yang equations do not play any role in engineering excited state TBA equations via the contour deformation trick. We further argue that the TBA equations are in fact written not for a particular string state but for the whole superconformal multiplet, and, therefore, the psu(2,2|4) invariance is built in into the TBA construction.Comment: 28 pages, 1 figure, v2: misprints are correcte

    Semiclassical strings in AdS(3) X S^2

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    In this paper, we investigate the semiclassical strings in AdS(3)XS^2, in which the string configuration of AdS(3) is classified to three cases depending on the parameters. Each of these has a different anomalous dimension proportional to logS, S^(1/3) and S, where S is a angular momentum on AdS(3). Further we generalize the dispersion relations for various string configuration on AdS(3)XS^2.Comment: 15 pages, added reference

    Multimodal particle size distribution or fractal surface of acrylic acid copolymer nanoparticles: A small-angle X-ray scattering study using direct Fourier and indirect maximum entropy methods

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    Acrylic acid copolymers are potential carriers for drug delivery. The surface, surface rugosity and the absolute dimension of the particles are parameters that determine the binding of drugs or detergents, diffusion phenomena at the surface and the distribution of the carrier within the human body. The particle-size distribution and surface rugosity of the particles have been investigated by small-angle X-ray scattering and dynamic light scattering. Direct Fourier transform as well as a new strategy for the indirect maximum-entropy method MAXENT are used for data evaluation. Scattering equivalence of a pure multimodal distribution of hard spheres (five populations) and a mixed multimodal-surface-fractal model (four populations) was found. Model calculations and dynamic light-scattering experiments gave evidence of the multimodal particle-size distribution combined with the fractal surface of the carrier The main moiety consists of particles 90 nm in diameter which are surface fractals in the 10 nm region
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